1. Field of the Invention
The present invention relates to a recording/reproducing apparatus for television ("TV") image and the like, and, particularly, relates to a video tape recorder ("VTR") for simultaneous recording/reproducing of multiple TV signals.
2. Description of the Prior Art
In general, this type VTR records on a video tape a TV signal received by a TV antenna or from a TV camera and reproduce the TV signal from the video tape according to an instruction by the user. The term "TV signal" used herein after includes video and audio signals.
This type VTR structurally includes a signal system and a mechanical system. The signal system further includes a TV signal processing system and a control signal processing system.
FIG. 1 shows the schematic diagram of a conventional VTR having such TV signal processing and control signal processing systems. The TV signal processing system includes a TV tuner 1 and a signal processing circuit 2. TV tuner 1 is disposed either inside the VTR or outside. In general, a single TV tuner 1 is provided. Signal processing circuit 2 performs various signal processing operations for recording and reproducing for luminance and color signals contained in the TV signal of a channel selected by TV tuner 1 whereby the TV signal can be sent to a tape head 4 included in a mechanical system 3. Signal processing circuit 2 also generates a reproducing signal which can be sent to a CRT (not shown). The description of signal processing circuit 2 is well known.
The control signal processing system includes an operation circuit 5, a timer circuit 6 and a system controller 7. Operation circuit 5 generates various instruction signals which correspond to the contents of instructions given by various operation buttons related to recording and reproducting. Timer circuit 6 sets reservation of video recording and the like. System controller 7 serves as a general controller which generates various control signals to operate, inside the VTR, electrically and mechanically in the order corresponding to the purposes of use in the recording and reproducting.
Mechanical system 3 has a tape head 4, a tape head actuating mechanism with a servo system thereof (not shown), and a tape loading mechanism (not shown). Mechanical system 3 is controlled by system controller 7.
A series of operations of a conventional VTR will be described hereinafter.
When a recording mode of the VTR is selected with a video tape 8 being loaded, the TV signal of one channel or station selected by TV tuner 1 is fed to signal processing circuit 2. Signal processing circuit 2 performs signal processing necessary for recording and then feeds the processed TV signal to tape head 4 to actuate tape head 4. By the actuation of tape head 4, the processed TV signal is then recorded magnetically on the video tape 8.
When a reproducing mode of the VTR is selected, a TV signal is reproduced from video tape 8, via tape head 4, in a reverse order to the aforesaid recording mode of operation, so that the TV signal is fed to the CRT.
Such conventional VTR has a problem in that a multiple number of TV signals or programs cannot be recorded/reproduced simultaneously in the same time slot.
For example, assume there are three video recording reservations set by timer circuit 6, as shown in FIG. 2. The time slots of RESERVE 1 and RESERVE 2 do not overlap, but the time slots of RESERVE 2 and RESERVE 3 partially overlap during a time period from 9:00 to 10:00. Since the conventional VTR is not capable of simultaneously recording more than one TV programs in the same time slot, either RESERVE 2 or RESERVE 3 must be selected during this overlapping time period. For example, if RESERVE 3 is set to have a higher priority than RESERVE 2 during this overlapping time period, the recording of RESERVE 2 will stop at 9:00 and the recording of RESERVE 3 will start at that time, as shown at the bottom portion of FIG. 2.